Frequency and consequences of ventricular hypertrophy in pregnant women with treated chronic hypertension

Background Ventricular hypertrophy is a known sequela of long-standing chronic hypertension with associated morbidity and mortality. Objective We sought to assess the frequency and importance of left ventricular hypertrophy in gravidas treated for chronic hypertension during pregnancy. Study Design This was a retrospective study of pregnant women with chronic hypertension who were delivered at our hospital from January 2009 through February 2015. All women who were given antihypertensive therapy underwent maternal echocardiography and were managed in a dedicated, high-risk prenatal clinic. Left ventricular hypertrophy was defined using the criteria of the American Society of Echocardiography as left ventricular mass indexed to maternal body surface area with a value of >95 g/m². Maternal and infant outcomes were then analyzed according to the presence or absence of left ventricular hypertrophy. Results Of 253 women who underwent echocardiography, 48 (19%) met criteria for left ventricular hypertrophy. Women in this latter cohort were significantly more likely to be African American (P =.031), but there were no other demographic differences. More than 85% of the entire cohort had a body mass index >30 kg/m² and a third of all women had class III obesity with a body mass index of >40 kg/m². Importantly, duration of chronic hypertension (P =.248) and gestational age at time of echocardiography (P =.316) did not differ significantly between the groups. Left ventricular function was preserved in both groups as measured by left ventricular ejection fraction (P =.303). Those with ventricular hypertrophy were at greater risk to be delivered preterm (P =.001), to develop superimposed preeclampsia (P =.028), and to have an infant requiring intensive care (P =.023) when compared with women without ventricular hypertrophy. These findings persisted after adjustment for age, race, and parity. The gestational age at delivery according to measured left ventricular size was also examined and with increasing ventricular mass there was a significant association with the severity of preterm birth (P <.001). Conclusion Left ventricular hypertrophy was identified in 1 in 5 women given antepartum treatment for chronic hypertension. Further analysis showed that these women were at significantly greater risk for superimposed preeclampsia and its attendant perinatal sequelae of preterm birth.